lightford



Jkrdf' CW J. F. L'IGHTPORD.

STEAM TRAP.

Patented Mar. 26, 1889.

(No Model.)

5o tral internally-sorow-threaded collar, a.

UNITED STATES PATENT OEEIcE.

JOHN F. LIGHTFORD, OF PORTLAND, MAINE, ASSIGNOR TO THE SEWALL SAFETY CAR HEATING COMPANY, OF SAME PLACE.

STEAM-TRAP.

SPECIFICATION forming part of Letters Patent No. 400,349, dated March 26, 1889.

Application filed May 25, 1888. Serial No. 275,105. (No model.)

To aZZ whom it may concern;

Be it known that I, J OHN F. LIGHTFORD, of Portland, county of Cumberland, State of Maine, have invented an Improvement in Steam-Traps, of which the following description, in connection with the accompanying drawings, is a specification, like letters on the drawings representing like parts.

This invention has for its object to construct a steam-trap which shall be very sensitive and effectual in operation.

The invention consists in a steam-trap having a cylinder or shell containing at its lower end a thermostatic vessel and bottom plate, the thermostatic vessel consisting of an inverted cup-shaped device secured by flanges between the shell and bottom plate, and a valve or plunger resting upon the diaphragm of the thermostatic vessel and co-operating with a valve-seat in the upper end of the shell, the shell further having outlets for the water of condensation at or near the thermostatic vessel, the whole being constructed and arranged substantially as hereinafter more particularly set forth and claimed.

The drawing shows in vertical section a steam-trap embodying this invention.

The shell or case a, made cylindrical, is interiorly screw-threaded at its lower end, as at a, to receive the bottom plate, b. An annular flange, a is formed upon the interior of the shell to adjacent to the screw-threaded portion a. The thermostatic vessel employed consists simply of a sheet of metal struck up bysuitable dies to form a shell, 0, having the outwardly-projecting flange c. The shell 0 is of suitable diameter to enter the case a at thelower end, the flange c resting upon the flange a The shell 0 is held rigidly in position by the bottom plate, I), which clamps or presses down firmly upon the flange c. The shell cand the bottom plate together form the thermostatic vessel, which will be filled with any suitable material. The shell to has near its lower end, as at a point just above the flange a the series of openings a for the exit of water of condensation. The shell a at its upper end is screw-threaded, as at a, to receive a cap or top plate, a having a cenpering plug, d, is placed in the shell a, the

reduced end of which enters the central opening of the cap a so that this tapering portion may come in contact with the valve-seat when desired. The plug d has attached to it at its lower end or formed integral with ita spider, d which bears upon the diaphragm of the thermostatic vessel 0, so that as the said diaphragm expands and contracts the plunger d will be moved vertically. The ends of the arms of the spider are bent downwardly, as at 61 to embrace the side walls of the thermostatic vessel. By this construction the steam entering the cylinder or shell a causes the thermostatic vessel 0 to expand, and thereby close theopening into said shell; but as the diaphragm contracts by the cold the said plunger is-allowed to fall, thereby opening the said passage into the cylinder or shell and permitting the water of condensation to enter, which immediately escapes through the exit-passages a It will be observed that by locating'the exits a directly opposite the thermostatic vessel the diaphragm will be exposed to the best advantage. It will also be seen that by employing the screw-threaded cap and shell and locking-ring or coupling a the shell or case a may be adjusted vertically, as desired, in contradistinction to adjusting the thermostatic vessel. The thermostatic vessel 0 is made as an inverted cup, the lip of which is made as a flange, and the bottom plate, I), of the shell closes its open end. Thus constructed it is distinguished, on the one hand, from a flat diaphragm closing a chamber in the bottom plate, and, on the other hand, from a tight box or vessel suspended in the shell.

I claim 1. In a steam-trap, the cylinder or shell a, containing at its lower end the thermostatic vessel and at its upper end the valve-seat, the thermostatic vessel consisting of an invertedcup-shaped device secured by flanges to the plunger having guides at each end, substantially as described.

I). In a steam-trap, the shell (1, having the flange (6 and the bottom plate, I), combined with the inverted-cup-shaped shell 0, having the flange 0, which, together with the said :0 bottom plate, forms the thermostatic vessel,

substantially as described.

a. In a steam-trap, the shell a, having exits, the bottom plate, I), and shell 0, combined with the vertically-movable plunger d, having the spider (Z spanning the diaphragm of the shell 0, substantially as described.

5. In a steam-trap, the shell at, having lateral exits of, the bottom plate, I), and the inverted-cup-shaped shell 1:, rising above the bottom plate in front of the exits and secured by its flange between the shell a and bottom plate, combined with a valve moved by the said shell 0, and the top plate and cap a", substantially as described.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

JOHN F. TJGI'lTlIliORl').

, \Vitnesses: 7

Lines II. SEWALL, BENJ. THOMPSON. 

